For an instructor lead, in-depth look at learning SQL click below.
If you’re looking to understand database design principles, SQL is a language you can’t afford to neglect. SQL, or Structured Query Language, is a powerful tool used to interact with relational databases. Not only does it allow you to query data, but it also allows you to design and create databases from scratch.
Different Kinds of SQL Courses Available
There are plenty of courses out there welcoming beginners, through intermediate to professionals. They all aim to teach database design principles. Some are basic courses that teach SQL syntax, while others are more advanced, teaching you how to design and implement complex database systems.
Courses for Beginners
For beginners, there are several online courses that cover the basics of SQL. Many of these use SQLite as it is simple and easy to learn on. Here’s an example of what you might learn to do with SQL in one of these courses:
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-- Retrieve all records from a table SELECT * FROM employees; -- Filter records using a conditional statement SELECT * FROM employees WHERE salary > 50000; |
Courses for Intermediate Learners
For those who have mastered the basics and want to dive a little deeper, intermediate-level courses are a perfect choice. They explore SQL in more depth, often using more complex databases like MySQL or PostgreSQL. Here’s an example of something you’d learn in an intermediate SQL course:
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-- Combine rows from two tables based on a related column SELECT orders.order_id, customers.customer_name FROM orders JOIN customers ON orders.customer_id = customers.customer_id; |
Advanced SQL Courses
Advanced courses can take you even further, teaching you to write complex queries and design efficient databases. Here’s something you’d learn in an advanced SQL course:
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-- Create a VIEW that provides a subset of data from one or more tables CREATE VIEW employee_overview AS SELECT employee_id, first_name, last_name, department FROM employees WHERE hire_date > '2005-01-01'; |
Pick the Course That’s Right for You
Choose the course that’s right for your needs and knowledge level. With the right course, you will be well on your way to understanding the design principles needed for working with databases in SQL.